Toy locomotive sound effects



April 21, 1959 w, sMlTH I 2,882,834

I TOY LOCQMOTIVE SOUND EFFECTS Filed May 3, 1955 *-L ..l 7 T a??? v 0 30/5 s 5 g n" ATTORNEY TOY LOCOMOTIVE SOUND EFFECTS William R. Smith,Hamden, .Conn., assignor to The A. C. Gi be C mp ny, New H ven, Conn 2co p ra io M ryland Application May 3, '1956,'SerialNo. 582,584 4 C ams- (Cl- -150) This invention relates to toy or model electric railroadsparticularly of miniature size whose rolling stock comprises alocomotive externally styled to resemble either a one-unit or two-unitdiesel locomotive carrying sound producing means from which will emanatenoises realistically simulating the pulsating roaring sound of a dieselengine and also familiar variations of such sound that accompany changeof engine speed. The invention also relates to electrical systems whichenable the same sound producing means on occasion to produce asignalling sound simulating that of a diesel horn.

object of the invention is to produce the aforesaid characteristics ofsound by the use of very small electri a y energ ze app tus us p l ofbeing ontained by and concealed within the more miniature sizes of toyor model railroad rolling stock whether running on two-rail orthree-rail track.

Another object is to subject the train-carried sound producer to thesame increases and decreases of electrical potential that are impressedon the track rails for enerig'izing the propulsion motor of thelocomotive for controlling its speed of travel, so that the pulsatingcharacter of the aforesaid roaring sound will vary automatically inaccordance with changes in the speed of unnin o th t a .f m e eh e e i t.e d e locomotives in real railroading.

Anothe o j is to n o pora e the prep le q me e in one piece of rollingstock and the sound producing devices in a separate piece of rollingstock coupled thereto, such rolling stock being externally fashioned toresemble .a two-unit locomotive.

.A st ur e a m .i t accomp is al of the o ego'ing objectives by circuitsystems incorporating balanced resistance and capacitance and requiringonly a two-rail track capable of being energized by alternating ordirectcurrent at selected voltages varying say from 4 volts to volts, inresponse to which variation of voltage the speed of the train and therapidity of pulsation and strength of the diesel roaring will increaseand decrease in unison. Moreover the diesel imitating sound willcontinue realistically in subdued form, with dirnin: ished loudness andslowed rate of pulsation, when the propulsion motor is actually stoppedas when the train is standing at a way station.

A further objectis to provide the sound producing cirsuit with anelectrical cutout that can be set to silence the diesel roar and whichwhen so set permits the propuision motor still to operate without soundeffect and also leaves vthe train carried sound producer still able toemit the signalling noise .of a diesel horn whenever the current fed tothe track from the power circuit is pulsated by means of anelectromagnetic vibratory circuit ,interrupteras in the tracksideelectrical apparatus shown in my copending patent application Serial No.362,082, now US. Patent No. 2,826,996, issued March '18, 1958, owned'bythe assignee of the present application.

An object contributary to the above aims is to supplement the signalsound producing system disclosed in the aforesaid patent applicationwith an additional electromagnetic vibratory circuit interrupter carriedon the rolling stock operating with relatively very low frequency and soconnected in circuit as to afiect only the current reaching theminiature sound producing loud spealrer and not the current delivered tothe locomotive propul sion engine, whereby the loud speaker may beirnpulsed to emit a toneless, roar imitating noise and yet stand readyat any time to respond to the relatively high he quency circuitinterruptions of the trackside vibrator for sounding its horn imitatingtonal signal.

The foregoing and other aims and objectives oi the invention will becomeapparent in fuller detail from the following description of a preferredembodiment of the improvements said description having reference to theappended drawings wherein:

Fig. 1 shows a two-unit diesel locomotive of a toy or model trainstanding on toy railway track and equipped to produce soundrealistically imitative of the growling roar of a diesel engine as wellas on occasion the signalling noise of a diesel horn.

Fig. 2 is a plan view of the trailing or B- uni t of the locomotive withits car roof broken away to expose internal diminutive sound producingapparatus.

Fig. '3 is a View taken in section on planes fil -3+3 in Fig. 2 lookingin the direction ofthe arrow-s.

Fig. 4 is a diagram of wiring connections.

Figs. 5 and 6 are oscillograph curves showing typical wavecharacteristics of the current that energizes the sound producer tocause it to emit a pulsating roaring noise imitative of a diesel engine.i

In Figs. 1 and 4 the A-unit of a miniature diesel locomotive isrepresented at 12. Its propulsion motor 13 may be universal foroperation on alternating or direct current. If alternating current isemployed, starting, stopping and reversal of the direction pr trainrunning may be governed by the stepping action of an electromagneticmotor reversing relay 14 as is conventional and explained for instancein U .8. Patent No. "2,196,319. If direct current is employed thestepping relay 14 can be emitted and the direction of trail travelreversed by merelyreversing the polarity of the track rails 15 and'lfi.In either case it will-be understood as indicated "by electricalconnections in Fig. 4 that the propulsion motor 13 derives itsenergizing current from the track rails :15, 16 through relativelyinsulated traction wheelson respec- -tively opposite sides of thelocomotive -in conventional manner.

The sound producing apparatus in the B-unit -20 of the locomotivederives energizing current from the track rails 15, 16 in the samemanner. As an illustrative source of current supply a train controller-21 is represented in Fig. 4 having a 7 /2 -volt binding post 19- inconstant electrical connection with a manually swung voltage varyingtake-oli arm 22 that sweeps selective lengths of the train runningsection '23 of the higher voltage portion of the secondary winding of atoy transtorrner in the controller 21. The base or zero voltage "bindingpost of the controller is represented at 17 and the full potential or 15volt binding post at :18. The primarywinding 24 of thetransfornierderives :power from any suitable source of alternating current,preferably at 60 cycles, through an attachment cord 25 where- -bythecontroller can be stationedinan-y desired position at the track side ofthe railway ior manually governing the speed and direction of running ofthe train in the usual way through a circuit that includes normallyclosed contacts, one on reed 62 and one stationed at 64, in the highfrequency electromagnetic vibratory ,cirouit interrupter 35. When thereed 62 :is idle, train running, vnormally uninterrupted alternatingcurrent reaches the track rails 15 and 16 at voltages selective between4 and 15 volts through a circuit traceable in Fig. 4 as 17, 16, 15, 62,64, 19.

The sound producer 30 of the present improvements is mounted on theinterior of the B-unit 20 of the locomotive and may take the form of amagnetic speaker either of the horn type or the cone type, butpreferably shall be of the dynamic loud speaker type incorporatingeither a permanent type of field magnet or a solenoid energized fieldmagnet 33 as indicated in Fig. 4. Structural details of the speaker orsound producer 3!) are not herein shown because they may be similar tothe corresponding unit shown in a copending application of Raymond E.Smith, Serial No. 251,426, filed October 15, 1951 now U.S. Patent No.2,791,972 issued May 14, 1957. The basic elements of the speaker are anelectromagnetically incited vibratory air wave inducing, disheddiaphragm or cone 31 having a voice coil 32 and the electromagnet 33whose core may be replaced by a permanent magnet as well understood inthe art. For purposes hereinafter explained in fuller detail there isplaced series with the speaker 30 a resistor 47.

When, as is fully explained in my aforesaid U.S. Patent No. 2,826,996,it is desired to energize speaker 30 to produce a horn imitating signalsound, normally open momentary switch 38 will be manually closed todirect. 15 volts from controller 21 through the magnet coil 36 ofvibrator 35 which causes reed 62 to vibrate at the relatively highfrequency of the alternating current derived from controller 21. Thecurrent delivered to track rails 15, 16 and hence to speaker 30 is thusintermittently broken and remade at least twice during each excursion ofthe reed through the breaking and making of contact by the reed not onlywith the aforesaid stationed contact 64 but also with an additionalcontact 65 stationed at the opposite side of the reed. This however doesnot interfere with the running of the train nor control of train speedbecause the vibrator interrupted current continues impressed upon thetrack through a circuit traceable in Fig. 4 as 17, 16, 15, 62, 64 or 65and 19 or 18.

Figs. 2, 3 and 4 show interpositioned in only the speaker circuit a lowfrequency electromagnetic vibratory circuit interrupter 40 comprising areed 41 normally displaced laterally from alignment with its driving,solenoid 42 in its idle position so as normally to close a circuitbetween a contact 43 resiliently carried by the reed and a resilientlystationed contact 44 forming vone electric terminal of the solenoid 42.At the same time another contact 45 resiliently carried on the oppositeside of need 41 ,is separated from another resiliently stationed contact46 which connects to the aforesaid resistor 47. The general arrangementof the contacts may be as in my U.S. PatentNo. 2,826,996. An overallhookup of the circuits is illustrated in Fig. 4 and their cooperativerelationship hereinafter more fuller described.

.Fig. 3 shows that the mounted end of reed 41 and of the stationedspring leaf contacts 44 and 46 are held in insulated relation by acommon base structure 49 that is secured to the sheet metal floor 48 ofthe B-unit 20 which floor of the rolling stock also supports the soundproducer 30.

Further carried on car floor 48 there is a cutout switch 54 comprisingan insulated circuit terminal 55 and a swingable switch arm 56 having aconductive circuit making and breaking end 57 and a handle end 58, thelatter extending through an aperture 59 in the car floor to becomeaccessible for setting the switch in ON or OFF position when the rollingstock is removed from the track and turned upside down.

The circuiting of the train carried components of the electrical systemcan be traced in Figs. 2, 3 and 4 as follows.

Alternating current fed to track rails15, 16 from the controller bindingposts 17 and 19 whether continuous and uninterrupted while signalenergizing switch 38 is open or whether interrupted by the signalcausing vibration of reed 62 when switch 38 is closed, serves toenergize the magnet coil 42 of the train carried low frequency vibrator40 through the medium of normally closed, reed opened contacts 43 and44. The coil energizing A.C. circuit can be traced in Fig. 4 as 16, 42,44, 43, 49, 54 and 15. When silencing switch 54 is set in open positionvibrator 40 remains idle and without effect on sound producer 30 whichthereupon is left operatively responsive only to current derived fromtrack 16, 15 through a capacitor 34 that is capable of building up asignal sounding energization of speaker 30 responsive to interruptionsof track current by vibrator 35 as is fully described in my aforesaidU.S. Patent No. 2,826,- 996. Thus whether silencing switch 54 is open orclosed speaker 30 can be made to emit a horn or whistle imitating tonalsound at any time by manually closing signalling switch 38.

When the silencing switch 54 is set in closed position there willconstantly be emitted by speaker 30 the pulsating sound of a dieselengine that is new with this invention. To accomplish such effect uponspeaker 30 the reed vibrated contacts 45, 46 open and close atrelatively very low frequency to make and break a circuit through theresistor 47. This circuit can be traced in Fig. 4 as 16, 32, 47, 46, 45,54 and 15.

Starting from its position in Fig. 4 reed 41 will be drawn towardalignment with its motivating solenoid 42. Owing to the springy natureof the driving contacts 43, 44, they will remain closed until bymomentum reed 41 has lunged beyond a position of alignment with itssolenoid thus causing circuit to be made between contacts 45 and 46.This imparts an impulse to the voice coil 32 of the air wave generatingdiaphragm or cone 31 in speaker 30. Contacts 43, 44 immediately separateand the natural spring bias in reed 41 returns to its starting positionin Fig. 4 thus breaking the speaker circuit at contacts 45, 46 andreclosing the solenoid energizing contacts 43, 44. This cycle of reedexcursion automatically repeats at a very low frequency opening andclosing contacts 45, 46, say, three to sixty times per second. Factorsdetermining the low frequency of circuit interruptions caused by reed 41are the thickness, length and stiffness of reed 41, and the spacesetting of the reed driving contacts 43, 44, in other words a compositeeffect of the natural mechanical resonance of the reed and thepositional setting of the reed driving contacts.

Regardless of the mechanical resonance of the reed, the frequency of itsexcursions will vary with the reed driving strength of the magneticfield of solenoid 42 which in turn varies in accordance with differentvoltages impressed on the track rails 15, 16 by the train speedcontrolling manipulation of take-off arm 22 in controller 21. Thus whenthe track voltage is raised from 4 volts toward 15 volts the reed willvibrate proportionally faster and this will increase correspondingly therapidity of the pulsations of the diesel engine sound emitted by thespeaker. At the same time, other characteristics of the sound willchange because of accompanying change in the proportional periods oftime during one reed excursion that the speaker affecting contacts 45,46 remain open or closed. The springiness in each of the reed motivatedcontacts accommodates differing degrees of overthrow of reed 41 past itsposition of alignment with solenoid 42. This varies the saidproportional periods of time and consequently the depth and intensity ofnoise emitted by speaker. The sound is found to rise to a crescendo andhigher pitch as higher voltages are delivered to the track.

A further condition, namely that speaker 30 is fastened to the thinreverborative sheet metal floor 48 of the car, causes the inciting ofspeaker cone 31 by relatively slow circuit interruption to produce asounding board etfect in the sheet metal 43 that augments the loudnessand depth of the sound emitted by the speaker for simulating thepulsating exhaust roar of a diesel engine.

Without implying that the elements of the electrical system must possessdefinite electrical ratings the re sistor 13 may to advantage be ratedohms-l watt when a permanent field magnet instead of the electromagnet33 is used in the speaker Sll. In such instance the resistor may bereplaced by a condenser rated mfd.-15 volts-of the electrolitic type.Either will serve to check excessive current supply to the speaker andwill filter out frequencies derived through the track from the tracksidecurrent supply if vibrator 4% should be substituted for vibrator as aWay of causing the train carried speaker to fail to match the naturalmechanical resonance of the cone or diaphragm in the speaker. In eithercase there results an erratically broken current wave as is shown by theoscillographs of Figs. 5 and 6 which is productive of the desiredtoneless pulsating noise emitted by the speaker imitative of the exhaustsound of a diesel engine. The capacitor 34 may be rated in theneighborhood of 100 mfd.-l5 volts for protection of the voice coil ofthe speaker.

The propulsion motor 13 and its automatic direction reversing stepswitch 14 may be carried on the same locomotive chassis 20 with thesound producing apparatus in the event that a single unit diesellocomotive is to be simulated by the exterior fashioning or" the toyrolling stock.

As various obvious departures from and substitutions can be made for theexact circuiting and composition of electrical elements proposed in theherein disclosed example of an embodiment of the invention, the appendedclaims are directed to and intended to cover all such departures andsubstitutions as come within a broad interpretation of the wording ofthe claims.

I claim:

1. An electrical system for operating a toy electric train and causingto emanate therefrom substantially toneless sounds simulating thepulsating exhaust noise of a diesel engine, comprising in combination,toy track rails, a source of electrical energy, means for varying thepotential of said source of electrical energy, means to connect saidvariable source across said rails, toy rolling stock riding on saidrails equipped with means to collect current therefrom derived from saidsource, conductors connected to said collector means carried by saidrolling stock electrically associated to form a plurality of parallelload circuits, a train propulsion motor carried by said rolling stock ina first one of said parallel load circuits, sound producing apparatuscarried by said rolling stock in a second one of said parallel loadcircuits including an electrodynamic loud speaker having n we a voicecoil, circuit making the breaking contacts in series with said voicecoil, a resilient magnetically attractable reed mechanically connectedwith said contacts to open and close the same and normally biased towarda flexed position causing said contacts to be open, an electromagnetstationed relatively to said reed to exert magnetic attraction thereonin a direction away from said flexed position, said electromagnet havingan electric winding connected across said rails for deriving currentfrom said track rails at varying potential determined by said variablesource of electrical energy, and auxiliary contacts electricallyconnected in series with said winding to make and break the supply ofcurrent to said winding mechanically connected with said reed to beopened and closed by the flexing thereof at a periodicity determined atleast in part by the potential of current in said track rails.

2. An electrical system as defined in claim 1, in which the said speakerincludes an airwave inducing diaphragm having a mechanical resonancediscordant with the frequency of vibration of said reed, thereby todefeat evenness in the vibrations of said diaphragm and impart irregularfluctuation thereto resulting in the emission of a substantiallytoneless pulsating noise by said speaker.

3. An electrical system as defined in claim 1, togetherwith a thirdcircuit in branching relation to a portion of the said second circuitand containing the said speaker to the exclusion of the saidelectromagnetically powered means, a capacitor in said third circuit inseries with said speaker, additional automatic circuit interruptingmeans electrically connected and manually operable at will to supply tothe said track rails a current pulsating regularly at frequenciessuiiiciently higher than the circuit interrupting frequency of saidelectromagnetically powered means to cause said speaker to emit a tonalsignalling sound.

4. An electrical system as defined in claim 3, together with a noisesilencing switch in the said second circuit having a switch operatinghandle protruding outside the said rolling stock to be manuallyshiftable between open or closed positions.

References Cited in the file of this patent UNITED STATES PATENTS1,303,117 Roe May 6, 1919 2,313,379 Wood Mar. 9, 1943 2,459,038 McKnightJan. 11, 1949 2,645,768 Santino July 14, 1953 2,791,972 Smith May 14,1957 2,792,409 Smith May 14, 1957 2,826,996 Smith Mar. 18, 1958 UNITEDSTATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 2,882,834 April21, 1959 William R0 Smith It is hereby certified that error appears inthe -printed specification ofthe above numbered patent requiringcorrection and that the said Letters Patent should read as correctedbelow.

Column 6, line 1, claim 1, for "circuit making the breaking contacts"read circuit making and, breaking contacts column 2, line 42, for

"emitted" read omitted Signed and sealed this 1st day of-Septemb'er1959.

(er-AL) Attest:

KARL H, AXLINE Attesting Oificer ROBERT C. WATSON Commissioner ofPatents

